NOTE: When you see that 1 or more users have different sync types (diary, task and contacts) you cannot save the ranks in 1 pass. Otherwise all users would end up with the same settings. In this case it's better to save it per user.

Select the 2nd group and use rank 2 for these users (repeat for other ranks).

Next you have to create a 2nd service. Go to the InfoBridge\Exchange Online Synchronizer\Prerequisites folder and copy the 'Install extra service.cmd' file into the Exchange online Synchronizer folder. Run the file by doubleclicking it (Run as Administrator is recommended).

The next step is to add ranks to the 2 services, please read this KB Article.

Create new shortcuts to the Synchronizer admin, one for each rank. Add the rank in the start command, e.g. "C:\program files\InfoBridge\Exchange online synchronizer\InfoBridge Synchronizer Administrator.exe" /S1

Start the admin and make sure the service options are correct, including the correct server id (which is the rank number)